Reinforced concrete.



PATENTED DEC. 27, 1904.

B. B. JARVIS.

REINFORCED CONCRETE. APPLIOATION FILED MAY zo. 1904.

,wdnes'ses 1 "Int tutor UNITED STATES Patented December 27, 1904,

, PATENT OFFICE.

EDGAR BEAUMONT JARVIS, OF TORONTO, CANADA.

REINFORCED CONCRETE.

SPECIFICATION forming part of Letters Patent No. 778,247, dated December27, 1904.

Application filed May 20, 1904. Serial No. 208,902-

of metal consistent with strength will be employed in the construction;and it consists, essentially, of a plurality of bars of increasinglength located one above the other and provided with end lips, theshorter bars being arranged intermediate of the length of the longerones and a plurality of stirrups held within the end lips and obliquelyset, so as to incline toward the ends of the beam, the parts beingotherwise constructed and arranged, as hereinafter more particularlyexplained.

Figure 1 is a perspective view of a beam partially broken away and insection to ex hibit the construction of my truss. -Fig. 2 is an enlargeddetail showing one section of the truss comprising a bar and stirrups.

In the drawings like letters'of reference indicate corresponding partsin each figure.

A is the cement beam.

B is the lower member or bar of the truss, Which is provided withrectangular inwardlyturned end lips I). v

A represents the stirrups, which are made in the shape of asubstantially rectangular loop bent at the lower end at 0, so as to givean oblique set to the stirrup in the direction of the ends of the beam.There is a stirrup located at each end-of the bar B.'

B, B and B are bars similarly formed,

sponding end of the bar under it. The lips formed by the ends of thebars form a locking-hook in the cement, which prevents the bar slippingand also serves to hold the stirrups in position, which form the ties totake the shearing strain. The greatest bending moment or tension of thetruss at the center, it will be seen, in construction is taken by themaximum depth of the bars, such depth decreasing as the bars approachthe end of the beam practically in proportion as the bending momentdecreases.

It will bereadily seen from the form of truss that I have designed thata maximum a minimum weight of metal.

I preferably provide the clampsD throughout the length of thebars, asindicated, and in proximity to the stirrups, so as to securely strengthis obtained in the cement beam with v hold them together not only whenin the beam,

but also for transportation. The clamps, as Well as the-end lips, serveto prevent the bars from slipping lengthwise on the concrete.

It will be readily understood that my device may be applied to columns.

What I claim as my invention is 1. A truss for cement beams comprising aplurality of bars of different lengths having inturned lips and locatedone above theother, the shortest being located in the center, and aplurality of obliquely-set stirrups held within the lips as and for thepurpose specified.

2. A truss for cement beams comprising a bar with end lips and stirrupsfitting within the lips and obliquely set as and for the purposespecified.

3. A truss for cement beams comprising a plurality of bars of differentlengths located one above the other, the shortest being located in thecenter, and a plurality of obliquely-set stirrups suitably held at theends of the bars as and for the purpose specified.

4:. In combination a plurality 'of bars of different lengths located oneabove the other, the shortest being located in the center, a pluraltheends of the bars and clamps for securing tending over the bars anddesigned to secure the bars together as and tor the purpose speelthemtogether as specified.

EDGAR BEAUMONT JARVIS.

o. The combination With a plurality of bars 5 of different lengthslocated one adjacent to the WVitnesses:

other, the shortest being located in the center, B. BOYD, and havingobliquely-set ends, of clamps eX- M. MOLAREN.

